Geographical Social Network Visualization Layout Algorithm Based on Spatial Location Coupling

In view of the problem that the traditional force-guided layout algorithm could not take into account the initial geospatial location characteristics of the node,this paper proposes the spatially coupled force-directed algorithm(SCFDA).While during layout,the node is affected by the Hulk gravity and the Coulomb repulsion,and also receives the boundary repulsion and central gravity from the spatial community it belongs to.As consequence,the node will adjust the layout and position under certain geographical space constraints.When calculating the center gravity,the internal degree of the node is taken into account,so that the nodes with higher internal degree are closer to the center of the spatial community.In calculating the boundary repulsion,the external degree of the node is taken into account,so that the nodes with higher external degree are closer to the boundary of the spatial community.Gowalla and Brightkite,the two of social network check-in datasets are used to conduct experiments with the consideration of internal degree and external degree.The comprehensive evaluation index value E(G)evaluates the results of the experiments.The horizontal comparison experiment result shows that the SCFDA E(G)value is about one-tenth of the traditional force-directed layout algorithm,which indicates more reasonable layout result when taking into account the spatial characteristics of the nodes with smaller value.The vertical comparison experiment result shows that the SCFDA is universal on different data sets and different data volumes.